Background: Symptom overreporting and malingering are a topic of utmost importance in the field of forensic assessment in cases of claimed posttraumatic stress disorder (PTSD). Individuals may be coached regarding the symptoms of the condition they claim and regarding malingering detection strategies. Symptom validity tests (SVTs) should be as resistant against such knowledge as possible.

Method: Healthy, well-educated volunteers were instructed to simulate how a person in a forensic examination may respond in order to convincingly feign mental disorder after a traumatic event. Four groups of these experimental malingerers (n= 20, each) were given different scenarios. In a 2 x 2 experimental design, they received either specific PTSD symptom information or not, and either a warning against exaggerating or not. Results: Using a regression based formula for the German version of the Impact of Event Scale–Revised, the majority of simulators were wrongly classified as PTSD patients; in performance tests, they also demonstrated cognitive impairment. However, 96 percent of the participants were correctly classified as malingerers when a multi-method approach of symptom validity assessment was used. The Structured Inventory for Malingered Symptomatology, the Morel Emotional Numbing Test, and the Word Memory Test performed well in identifying feigned PTSD, while the MMPI-2 Fake Bad Scale and the Reliable Digit Span did so to a lesser degree. Only three simulators who received symptom information and warning were able to pass all five symptom validity measures. Participants who received symptom information alone were not able to perform in a more convincing way. Conclusion: The results demonstrate that PTSD symptoms can easily be presented by healthy adults. Within the framework of this experimental analog study it was shown that feigned PTSD can be detected in most cases if a multimethod approach to symptom validity assessment is employed. The usefulness of symptom validity testing in real-world forensic evaluations has been demonstrated by a number of other studies (German J Psychiatry 2010; 13: 140-149).